Pressure vessel flange with antirotation rings



Dec. 29, 1959 HARVEY 2,919,048

PRESSURE VESSEL FLANGE WITH ANTI-ROTATION RINGS Filed Jan. '7, 1957INVENTOR. John F. Harvey BY L 24 24A 23A W ATTORNEY United StatesPRESSURE VESEL FLANGE WITH ANTI- RUTATIQN RWGS Appiication January 7,1957, Serial No. 632,857

2 Claims. (Cl. 220-39) This invention relates to a pressure vessel andmore particularly to a full open end vessel having a removable closuretherefor and means for resisting rotational moment of distortion of theend wall portion of the vessel in the vicinity of the upper closure zonethereof when an internal pressure is applied thereto.

Heretofore, the full open end type of pressure vessel having either aninteriorly or exteriorly seated removable closure therefor to seal thesame was normally provided with a flange or thickened Wall portionaround the upper closure end thereof to resist any tendency of the wallportion in the closure end zone from rotating or distorting when aninternal pressure was applied thereto, such resistance to rotation ordistortion being necessary to prevent loosening of the cover or closureand resulting leakage to occur thereat. While the flanged or thickenedwall portion heretofore used for resisting such rotational moment of thevessel walls adjacent the opening thereof is satisfactorily andeconomically feasible on relatively small vessels, or for medium vesselssubjected to relatively low pressures, the flanged or thickened wallconstruction is not satisfactory, practical or economical for pressurevessels having relatively large diameter closure openings and/or whichare subjected to relatively high internal pressures. The disadvantage ofincorporating the flange or thickened Wall structure to large diameterand/ or high pressure vessel is that the amount of material or flangerequired to resist the turning moment in a large vessel was exceedinglylarge and resulted in a relatively heavy, bulky and expensiveconstruction.

An object of this invention is to provide an economic and eflicientmeans for resisting the tendency of the upper closure wall portions or arelatively large pressure vessel against a moment of rotation when aninternal pressure is applied thereto.

Another object of this invention is to provide a relatively inexpensiveanti-rotation means which is relatively simple, inexpensive tomanufacture and positive in operatron.

The above objects and advantages of this invention are accomplished by apressure vessel having a substantially uniform wall thickness adjacentthe upper closure zone, i.e., a wall having substantially the sameinternal and external diameter as down in the body of the vessel inwhich resistance to the moment of rotation or distortion of the upperend portion of the vessel is accomplished by a novel anti-momentrotating means connected to and extending across the top of the vessel.According to this invention, the anti-moment rotating means includes aplate member provided with depending shear lug positioned inwardly ofthe marginal edge position thereof, the shear lug being adapted to seatin a cooperating recess formed in the upper end of the substantiallyuniform vessel Wall. According to this invention, the shear lug andrecess are provided with cooperating surfaces to insure positive contacttherebetween. Consequently, as the internal pressure is applied to thevessel, the tendency of the wall adjacent the upper closure end of thevessel from distorting I 2,919,048 Patented Dec. 29, 1959 outwardly issuccessfully and economically resisted by the anti-moment rotating meansof the instant invention.

A feature of this invention resides in the provision whereby the vesselwall adjacent the upper closure end requires no flange or thickenedportion, the wall portion in the end closure zone having substantiallythe same internal and external diameter as down in the body of thevessel.

Another feature of this invention resides in the provision of ananti-moment rotating plate in the form of an annular member or ringprovided with a depending shear lug adapted to be received in a recessformed in the upper end of the vessel to resist rotation of the endportion of the vessel.

Other features and advantages of the invention will be readily apparentwhen considered in view of the drawings and description in which:

Fig. 1 is a fragmentary, sectional view taken through the upper end of apressure vessel in accordance with the instant invention.

Fig. 2 is a sectional, detail, perspective, bottom view of the improvedanti-rotation ring in accordance with the instant invention, and

Fig. 3 is an enlarged view of detail A of Fig. 1.

In. accordance with this invention, there is shown in Fig. 1 of thedrawings, a pressure vessel 10 comprising a body portion 11 which isclosed at the bottom end (not shown) and provided with a full open end12 in the upper portion thereof, the open end being adapted to receive asuitable removable pressure seal closure 13. While the size and shape ofthe vessel according to this invention may assume any desiredproportions and is adapted for any purpose to which a pressure vesselmay be used, the instant invention has particular utility for relativelylarge pressure vessels and/or vessels adapted to be subjected torelatively high internal pressures.

It is a fact that in pressure vessels which are closed by a readilyremovable pressure seal closure and sub jected to an internal pressure,there is a tendency on the part of the vessel wall portion adjacent theclosure end zone thereof to be subjected to a moment of rotation and todistort causing the closure to become loosened and for resulting leakageto occur thereat. In the past, this difficulty has been avoided byutilizing relatively small size pressure vessels, that is, vesselshaving a diameter of less than 36" and by providing such vessels with aflange or thickened wall portion adjacent the closure end zone thereoffor effectively resisting the turning moment of the wall portionsthereat.

However, with the tendency toward the utilization of pressure vesselshaving a diameter greater than 36" and/ or vessels adapted to besubjected to relatively high pressures, for example pressures of 4,000lbs. per square inch, the practice of utilizing a flange or thickeningof the Wall adjacent the closure end zone of such contemplated pressurevessels has proven to be impractical and costly to manufacture. I

In accordance with this invention, as shown in Fig. l, the improvedpressure vessel of the instant invention is provided with a body portion11 having a wall thickness adjacent the closure end zone thereof whichis substantially equal in thickness to the wall portion making up themain body portion of the vessel. While the pressure vessel may be closedat its open end by either an externally or internally type of boltedcover or closure, in the illustrated form of the invention, a pressureseal closure 13 of the Bridgman type is illustrated. As shown, the upperwall portion of the vessel adjacent the closure end zone is providedwith an internal portion suitably threaded for receiving an externallythreaded securing ring 14. Extending from ring 14 by a plurality ofcircumferentially spaced bolts 15 extending therefrom is a floating plugor cover plate 16 which is adapted to form the closure for the vessel.As shown, the cover 16 is provided with a reduced portion 16aterminating in an inclined shoulder 16b which forms a conical seat forreceiving a sealing gasket 17. If desired, a pressure ring 18 isdisposed between the'cover 16 and the gasket 17. As the cover. 16 ofsuch vessel is quite heavy, a lifting lug 19 may be pro vided tofacilitate lifting of the cover.

In order to resist a tendency of the wall portion of the vessel adjacentthe closure end thereof from being subjected to a rotating moment whenan internal pressure is applied thereto, a novel anti-moment rotatingmeans 20 is utilized. According to this invention, the anti momentrotating means comprises an annular plate member illustrated as a ring21 which is adapted to be removably fastened to the top of the vessel bymeans having a plurality of spaced bolts 22 adjacent the outer peripherythereof. As shown in Figs. 2 and 3, the antirnoment rotating ringcomprises a central portion 21a and an outer marginal edge portion 21b,the former being provided with a relatively thicker cross sectional areathan that of the latter. Spaced inwardly of the outer periphery of themarginal portion 21b of the ring, the latter is provided with adepending shear lug 23 which in the illustrated form of the inventioncomprises a continuous, annular, depending lug which is adapted to seatin a recess 24 formed in the upper end of the vessel, the recess beingprovided with vertical walls 24a. As shown in Figs. 1 to 3, the innersurfaces 23a of the depending lug is inclined. Thus, it will be notedthat when the antirotation ring is positioned on the top of the vessel,the tapered surface 23a of the shear lug assures positive contactbetween the vessel body and the anti-rotation ring, Figs. land 3. Itwill be further noted that the inclined surface of the shear lug furtherpermits more liberal machining tolerances and increases the probabilityof maintaining positive contact between the surfaces of the lug and therecess. With the ring 21 in place on the end of the pressure vessel inthe manner illustrated, when an internal pressure is applied to thevessel, the ring tends to resist the outward rotational movement of theend wall of the vessel. Thus, it will be noted that a desirable featureof the anti-rotation ring according to this invention is that it enablesa more uniform loading to be exerted on the closure threads throughouttheir entire height. Furthermore, it will be noted that the vessel maybe more readily fabricated in that the body of the vessel is providedwith substantially a uniform wall thickness throughout its entire lengthand requires no buildup of additional material or flange portionadjacent the closure end zone thereof as heretofore required.Furthermore, the anti-rotation ring is of relatively simpleconstruction, easily manufactured and rendered positive in operation. Toaccommodate bolts 15, the ring 21 is provided with aperture 25.

While the instant invention has been disclosed with reference to aparticular embodiment thereof, it is to be appreciated that theinvention is not to be taken as limited to all of the details thereof,as modifications and variations thereof may be made without departingfrom the spirit or scope of this invention.

What is claimed is:

1. A pressure vessel for withstanding relatively very high internalpressures comprising a body having enclosing wall portions of uniformthickness, said body having an opening in one end having a diametersubstantially equal to the internal diameter of said body, the

4 enclosing wall portions defining said opening being provided withinternal threads, said wall portions having in the upper edge thereof acontinuous recess extending around said opening, a removable pressureclosure for sealing said opening, a securing ring threaded in saidopening for retaining said closure, means forming a fluid tight sealdisposed between said closure and securing ring, said securing ringbeing adapted to accommodate the longitudinal thrust exerted on saidclosure when an internal pressure is applied to the vessel, a readilyremovable plate ring disposed across the top of said body, said platering being independently connected to said body for resisting only theoutwardly rotational tendency of said wall portions so that uniformloading of said threads in the open end is assured as internal pressureis applied, said plate ring having a co-extensive annular depending,integrally connected, shear lug adaptable to seat in said recess, saidlug resisting in shear the force tending to outwardly rotate the wallportions defining said open end and fastening means for readilyconnecting and disconnecting said ring to and from said bodyindependently of said closure, said fastening means including aplurality of bolts having a relatively small bolting area in proportionto the forces resisted for securing said ring to the upper edge of thewall portion, said shear lug having an inclined surface to insurepositive contact between said body and ring.

2. A pressure vessel adapted to be subjected to a relatively highinternal pressure comprising a body having a closure zone adjacent oneend thereof, said body having an enclosing wall portion of substantiallyuniform thickness in the closure zone to define therein an openinghaving a diameter substantially equal to the internal diameter of saidbody, said wall having in the upper edge thereof a continuous'recessextending around said opening, a removable closure means sealing saidopening, said closure means resisting the longitudinal thrust of theforces acting within the vessel, a readily removable ring disposedacross the top of said body and independently connected thereto toresist only the outwardly rotational movement due to the lateral thrustof the forces acting on said wall portion adjacent the closure end whenan internal pressure is applied to the vessel, said ring having asubstantially co-extensive, integrally connected, depending annularshear lug on the bottom side thereof adapted to seat in said recess,andfastening means for readily connecting and disconnecting said ring toand from said body independently of said closure means, said fasteningmeans including a plurality of bolts having a relatively small boltingarea in proportion to the forces resisted for securing said ring to theupper end of the wall portion.

References Cited in the file of this patent UNITED STATES PATENTS

